Compound bow

ABSTRACT

A compound bow reduces the force required to draw a bowstring and increases the propulsive force when shooting an arrow. The bow comprises a main body having a handle grasped, and a pair of limbs coupled to the ends of the handle; a dual pulley including a main pulley rotatably installed on a rotation shaft fixed to one end of the main body, and an auxiliary pulley having a radius greater than that of the main pulley and rotatably installed on the rotation shaft; a cam installed to the main pulley; a balance cable; a stopper member; a cam cable; a driven pulley rotatably fixed to the other end of the main body; and a bowstring.

CROSS-REFERENCE TO RELATED APPLICATION AND CLAIM TO PRIORITY

This application claims the benefit of Korean Patent Application No.10-2009-0015473, filed on Feb. 24, 2009, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein byreference and to which priority is claimed.

FIELD OF THE INVENTION

The present invention relates to a compound bow and, more particularly,to a compound bow in which a force is mainly applied to an auxiliarypulley with a large radius when a bowstring is drawn so that a drawingforce is reduced and in which a force is mainly applied to a main pulleywith a small radius to project an arrow when the bowstring is restoredto the original state so that propulsive force of the arrow can beincreased.

BACKGROUND OF THE INVENTION

In general, a compound bow utilizes effect of a cam or a wheel such thata bowstring can be easily drawn without a large force, a shooting forceis increased to an arrow when shooting so that shooting speed of thearrow is fast and a very strong force can be exhibited. The compound bowis chiefly used for hunting.

The existing compound bow, as illustrated in FIGS. 1 and 2, includes analuminum handle 10, an upper limb 20 coupled with the upper side of thehandle 10, and a lower limb 26 coupled with the lower side of the handle10. Respective ends 22 and 28 of the upper limb 20 and the lower limb 26have slits 21 and 27, and a cam is installed between the slits 21 and 27to rotate about eccentric shafts 70.

The cam includes an upper cam 30 and a lower can 36, and a bowstring 50is connected between the upper cam 30, the end 28 of the lower limb 26,and the lower cam 36. A first cable 40 and a second cable 46 pass crosseach other.

A cable guard 60 is installed to a central side of the handle 10 in thelateral direction, and a slide 66 is installed on the cable guard 60 tomove on the cable guard 60. The bowstring 50 is inserted into the slide66.

The slide 66 is a device pushing the first and second cables 40 and 46to one side. If the first and second cables 40 and 46 are not pushed toone side, the bowstrings 50 collides with the first and second cables 40and 46 when shooting.

In the existing compound bow constructed as described above, when thebowstring 50 is drawn, the upper and lower cams 30 and 36 having theeccentric shafts 70 rotate and wind the first and second cables 40 and46 to draw respectively, and simultaneously the upper limb 20 and thelower limb 26 are bent and the slide 66 moves toward the end of thecable guard 60. At this time, the upper and lower cams 30 and 36 aredistorted.

In other words, as illustrated in FIG. 2, the upper cam 30 is coupled tothe end 22 of the upper limb 20 by the eccentric shaft 70, one end ofthe bowstring 50 is coupled with a large diameter recess 31, the firstcable 40 is coupled to a small diameter recess 32 and the end of thelower limb 26, the lower cam 36 is coupled with the end 28 of the lowerlimb 26 by the eccentric shaft 70, the other end of the bowstring 50 iscoupled with a large diameter recess 37 of the lower cam 36, and thesecond cable 46 is coupled to a small diameter recess 38 of the lowercam 36 and the end 22 of the upper limb 20.

Thus, when the bowstring 50 is drawn, the upper and lower cams 30 and 36rotate about the eccentric shafts 70. When the bowstring 50 is drawn andreleased such that portions with the largest diameter passes through avertical position about the eccentric shafts 70, the arrow obtains astrong propulsive force due to a strong resilient force of the bowstring50 fast returning to the original position.

However, the existing compound bow has a limit of reducing a forcerequired to draw the bowstring 50 and of increasing the propulsive forceto shoot the arrow when sizes of the large diameter recesses 31 and 37and the small diameter recesses 32 and 38 of the upper cam 30 and thelower cam 36 are fixed.

SUMMARY OF THE INVENTION

To overcome the above problems or inconvenience of the conventional art,it is an object of the present invention to provide a compound bow forreducing a force required to draw a bowstring and for increasing apropulsive force of shooting an arrow.

To accomplish the above object of the present invention, there isprovided a compound bow comprising a main body having a handle graspedby a user and a pair of limbs coupled to both ends of the handle; a dualpulley including a main pulley installed to rotate around a rotationshaft which is installed to one end of the main body and an auxiliarypulley having a radius greater than that of the main pulley androtatably installed around the rotation shaft; a driven pulley rotatablyinstalled on the rotation shaft which is installed at the other end ofthe main body; a cam installed to the main pulley; a balance cablehaving both ends respectively connected to the main pulley and theauxiliary pulley, and wound around the main pulley and the auxiliarypulley in the same direction; a connecting member including a balancecable pulley around which a middle portion of the balance cable is woundand which is positioned at a lower side thereof; a bowstring having oneend coupled to an upper portion of the connecting member, a middleportion wound around the driven pulley and the other end connected tothe main pulley, and being wound around the cam; and a cam cable havingone end connected to the other end of the main body and the other endconnected to the main pulley, and being wound around the cam when thebowstring is drawn for shooting an arrow.

A compound bow according to another embodiment of the present inventioncomprises a main body having a handle grasped by a user and a pair oflimbs coupled to both ends of the handle; a dual pulley including a mainpulley installed to rotate around a rotation shaft which is installed toone end of the main body and an auxiliary pulley having a radius greaterthan that of the main pulley and rotatably installed around the rotationshaft; a driven pulley rotatably installed on the rotation shaft whichis installed at the other end of the main body; a cam installed to themain pulley; a string pulley installed to rotate around the rotationshaft which is installed to one end of the main body and coupled withthe main pulley; a balance cable having both ends respectively connectedto the main pulley and the auxiliary pulley, and wound around the mainpulley and the auxiliary pulley in the same direction; a connectingmember including a balance cable pulley around which a middle portion ofthe balance cable is wound and which is positioned at a lower sidethereof; a bowstring having one end coupled to an upper portion of theconnecting member, a middle portion wound around the driven pulley andthe other end connected to the string pulley, and being wound around thestring pulley; and a cam cable having one end connected to the other endof the main body and the other end connected to the main pulley, andbeing wound around the cam when the bowstring is drawn for shooting anarrow.

A compound bow according to yet another embodiment of the presentinvention comprises a main body having a handle grasped by a user, and apair of limbs coupled to both ends of the handle; rotation shafts fixedto both ends of the main body, respectively; dual pulleys, eachincluding a main pulley rotatably installed on the rotation shaft fixedto one end of the main body, and an auxiliary pulley having a radiusgreater than that of the main pulley and rotatably installed on therotation shaft; cams, each installed to the main pulley; balance cables,both ends of which are connected to the main pulley and the auxiliarypulley and wound around the main pulley and the auxiliary pulley in thesame direction; connecting members, each including a balance cablepulley around which a middle portion of the balance cable is wound andwhich is positioned at one side thereof; a bowstring, of which both endsare connected to the connecting members; and cam cables, each having oneend which is connected to any one of both ends of the main body and theother end which is connected to the main pulley which is formed at therotation shaft installed to the other end of the main body, and beingwound around the cam when the bowstring is drawn for shooting an arrow.

A compound bow according to still another embodiment of the presentinvention comprises a main body having a handle grasped by a user, and apair of limbs coupled to both ends of the handle; a dual pulleyincluding a main pulley rotatably installed on a rotation shaft fixed toone end of the main body, and an auxiliary pulley having a radiusgreater than that of the main pulley and rotatably installed on therotation shaft; a cam installed to the main pulley; a balance cable,both ends of which are fixed to the main pulley and the auxiliary pulleyand wound around the main pulley and the auxiliary pulley in the samedirection; a stopper member, including a balance cable pulley which isinstalled at one end thereof and around which a central portion of thebalance cable is wound, and temporally fixing the balance cable when anarrow is shot; a cam cable having one end fixed to the other end of themain body and the other end fixed to the main pulley, and being woundaround the cam in the direction opposite to that of the balance cable; adriven pulley rotatably fixed to the other end of the main body; and abowstring having one end connected to the stopper member and woundaround the driven pulley, and the other end fixed to the main pulley andwound around the cam in the direction opposite to that of the cam cable.

Also, the stopper member includes a housing, to an upper portion ofwhich one end of the bowstring is coupled and to one side of a centralportion of which the balance cable pulley is rotatably installed; and astopper, formed at a lower side of the housing, including a locking hookby which a clip is caught to be temporarily fixed, wherein the clip ismounted at one side of the balance cable near to the main pulley fromthe balance cable pulley.

Preferably, the stopper is rotatably coupled to the housing, and furtherincludes a locker of a stepped shape so that the clip is fastened by thelocking hook by restricting the rotation of the stopper when the arrowis shot; and the stopper member further includes a trigger having alocking step which is formed at one end thereof and temporarily contactsthe locker of the stopper to control the rotation of the stopper.

Preferably, the trigger having the locking step formed at one endthereof is rotatably coupled to the housing; and the stopper furtherincludes a pushing section which is spaced at a predetermined distancefrom and protrudes from the locking hook so that an upper portion of theclip contacts the stopper for its rotation when the clip moves into thehousing; and a support, of which one end is engaged with the stopper,and of which the other end contacts the other side of the trigger torotate the trigger according to the rotation of the stopper and makesthe locking step be caught to the locker.

Preferably, the trigger further includes a contact which is formed atthe other end thereof and contacts the balance cable near to theauxiliary pulley from the balance cable pulley, by which the balancecable rotates the trigger to have the locking step be separated from thelocker when the balance cable is rewound around the main pulley and theauxiliary pulley after the arrow is shot.

Also, the auxiliary pulley further comprises a stopping pin which isinstalled to the auxiliary pulley and temporally contacts the main bodywhen the auxiliary pulley rotates by a predetermined angle such that theauxiliary pulley does not rotate further.

Also, the stopping pin is in a screw-coupled fashion and is fastened toa predetermined portion of a stopping pin slot formed in the auxiliarypulley.

Preferably, the stopping pin are covered with anti-vibration coverspreventing noise and vibration.

Also, the auxiliary pulley further includes an interference pin whichmoves along an movement hole formed in the main pulley.

Preferably, the interference pin is in a screw-coupled fashion and isfastened to a predetermined portion of an interference pin slot formedin the auxiliary pulley.

Preferably, the interference pin are covered with anti-vibration coverspreventing noise and vibration.

Preferably, the main pulley and the auxiliary pulley are eccentricallyinstalled on the rotation shaft.

Preferably, each of the main pulley, the auxiliary pulley, and thedriven pulley includes a guide recess, depressed from the outercircumference thereof, around which the balance cable or the bowstringare wound; and the auxiliary pulley includes a separation preventingunit protruding along the guide recess by a predetermined height toprevent separation of the balance cable.

Preferably, the main pulley further comprises an anti-vibration guidewhich is formed at one side of the outer circumference thereof and has aguide recess installed in the tangential direction of the outercircumference thereof.

Preferably, the cam includes a gradually curved portion with anarc-shape; a steep curved portion connected to one end of the graduallycurved portion and forming a steep curve such that the other end thereofbecomes near to the rotation shaft; and guide recesses formed in thegradually curved portion and the steep curved portion to guide the camcable and the bowstring.

Meanwhile, in the compound bow according to another embodiment of thepresent invention, the stopper member includes a housing having an upperportion to which the bowstring is connected, a central portion to whichthe balance cable pulley is rotatably installed, and a protrusionprotruding from the other side by a predetermined length at a lowerportion thereof; and a latch, fixed to the protrusion and having alocking hook for temporally fixing a locking ring which is installed atone side of the balance cable near to the main pulley from the balancecable pulley.

Preferably, the latch is rotatably coupled to the protrusion and furtherincludes a locker which is protruded to control a rotation; and thestopper member further includes a detent rotatably installed to theprotrusion and having a locking step temporally contacting the locker ofthe latch to control the rotation of the latch, and a knob pinprotruding toward the outside of the housing.

Preferably, the stopper member further includes a first torsion springpressing the latch to be rotated in the direction that locking hook islocked with the locking ring; and a second torsion spring pressing thedetent in the direction where the locker is supported by the lockingstep.

Preferably, the knob pin of the detent further comprises a release wirehaving one end to which the cam cable is connected and the other end towhich the knob pin of the detent is coupled such that the locking ringlocked by the locker is separated during the rotation of the detentafter an arrow is shot.

Meanwhile, a compound bow according to the other embodiment of thepresent invention comprises a main body having a handle grasped by auser, and a pair of limbs coupled to both ends of the handle; rotationshafts fixed to both ends of the main body, respectively; dual pulleys,each including a main pulley rotatably installed on the rotation shaftfixed to one end of the main body, and an auxiliary pulley having aradius greater than that of the main pulley and rotatably installed onthe rotation shaft; cams, each installed to the main pulley; balancecables, both ends of which are fixed to the main pulley and theauxiliary pulley and wound around the main pulley and the auxiliarypulley in the same direction; stopper members, each including a balancecable pulley which is formed at one side thereof and around which acentral portion of the balance cable is wound, and temporally fixing thebalance cable when the arrow is shot; cam cables, each having one endwhich is fixed to any one of both ends of the main body and the otherend which is fixed to the main pulley formed at the rotation shaftinstalled to the other end of the main body, and being wound around thecam in the direction opposite to that of the balance cable; and abowstring, of which both ends are connected to the stopper members.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features and advantages of the present invention will bemore apparent from the following detailed description in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a perspective view illustrating an existing compound bow;

FIG. 2 is a perspective view partially illustrating a cam installingunit in FIG. 1;

FIG. 3 is a perspective view illustrating a compound bow according to afirst embodiment of the present invention;

FIGS. 4 and 5 are exploded perspective views illustrating a main pulley,an auxiliary pulley, and a cam as shown in FIG. 3;

FIG. 6 is a view illustrating a modification that a bow string isconnected to another string pulley;

FIG. 7 is a perspective view illustrating a connecting member of thecompound bow according to the first embodiment of the present invention;

FIG. 8 is an exploded perspective view illustrating a stopper member ofa compound bow according to a second embodiment of the presentinvention;

FIGS. 9 to 12 are schematic views subsequently illustrating operatingstates of the stopper member when the compound bow is operated, in which

FIG. 9 illustrates a state of the stopper member before the bowstring isdrawn;

FIG. 10 illustrates a state of the stopper member when the bowstring isdrawn by a predetermined distance; and

FIG. 11 illustrates a state of the stopper member before an arrow isshot;

FIG. 12 illustrates a state of the stopper member after an arrow isshot;

FIG. 13 is a perspective view illustrating a compound bow according to athird embodiment of the present invention;

FIG. 14 is an exploded perspective view of a stopper member illustratedin FIG. 13;

FIGS. 15 to 17 are schematic views illustrating operating states of thecompound bow according to the third embodiment of the present invention,in which:

FIG. 15 illustrates a state before the bowstring is drawn according tothe third embodiment of the present invention;

FIG. 16 illustrates a state that the bowstring is drawn by apredetermined distance according to the third embodiment of the presentinvention;

FIG. 17 illustrates a state the bowstring is fully drawn according tothe third embodiment of the present invention;

FIG. 18 is a perspective view illustrating a compound bow according to afourth embodiment of the present invention;

FIGS. 19 and 20 are exploded perspective views illustrating a mainpulley, an auxiliary pulley, and a cam as shown in FIG. 18;

FIGS. 21 to 23 are schematic views illustrating operating states of thecompound bow according to the fourth embodiment of the presentinvention, in which:

FIG. 21 illustrates a state before the bowstring is drawn;

FIG. 22 illustrates a state that the bowstring is drawn by apredetermined distance;

FIG. 23 is a view illustrating a state that the bowstring is fullydrawn; and

FIG. 24 is a perspective view illustrating a compound bow according to afifth embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S)

Hereinafter, embodiments of the present invention will be described indetail with reference to the accompanying drawings.

FIG. 3 is a perspective view illustrating a compound bow according to afirst embodiment of the present invention, FIGS. 4 and 5 are explodedperspective views illustrating a main pulley, an auxiliary pulley and acam as shown in FIG. 3, FIG. 6 is a view illustrating a modificationthat a bow string is connected to another string pulley, and FIG. 7 is aperspective view illustrating a connecting member of the compound bowaccording to the first embodiment of the present invention.

As illustrated, a compound bow according to the first embodiment of thepresent invention comprises a main body 100 having a handle 102 graspedby a user and a pair of limbs 103 coupled to both ends of the handle102; a dual pulley including a main pulley 110 installed to rotatearound the rotation shaft 101 that is installed to one end of the mainbody 100 and an auxiliary pulley 120 having a radius greater than thatof the main pulley 110 and rotatably installed around the rotation shaft101; a driven pulley 190 rotatably installed on the rotation shaft 101that is installed at the other end of the main body 100; a cam 130installed to the main pulley 110; a balance cable 141 having both endsrespectively connected to the main pulley 110 and the auxiliary pulley120, and wound around the main pulley 110 and the auxiliary pulley 120in the same direction; a connecting member 360 including a balance cablepulley 161 around which a middle portion of the balance cable is woundand which is positioned at a lower portion thereof; a bowstring 142having one end coupled to an upper portion of the connecting member 360,a middle portion wound around the driven pulley 190 and the other endfixed to the main pulley 110, and being wound around the cam 130; and acam cable 143 having one end fixed to the other end of the main body 100and the other end fixed to the main pulley 110, and being wound aroundthe cam 130 when the bowstring 142 is drawn for shooting an arrow.

The main body 100 includes the handle 102 grasped by a user, a pair oflimbs 103 coupled to both ends of the handle 102 and having two branchesat their rear ends, and a rotation shafts 101 installed with the pulleyswhich are rotatably connected between the two branches at the rear endsof the limbs.

The dual pulley includes the main pulley 110 and the auxiliary pulley120, and is rotatably coupled to the rotation shaft 101 which is formedat one end of any one of the limbs 103. And, the balance cable 141 iswounded around the main pulley 110 and the auxiliary pulley 120, therebyboth ends of which are connected to the main pulley 110 and theauxiliary pulley 120, respectively.

The auxiliary pulley 120 has an approximately oval plate shape, and hasan eccentric through-hole 121 formed at the central region thereof intowhich the rotation shaft 101 is connected. The auxiliary pulley 120 hasa guide recess 122 formed on the outer circumference thereof with apredetermined depth and a predetermined length such that the balancecable 141 can be wound around the outer circumference. A separationpreventing unit 127 protrudes from one side of the guide recess 122 witha predetermined height along the guide recess 122, and preventsseparation of the balance cable 141. An arc-shaped stopping pin slot 124and an arc-shaped interference pin slot 125 are formed about thethrough-hole 121. The stopping pin slot 124 has a stopping pin 182 whichprotrudes by a predetermined height from the auxiliary pulley 120 andtemporally contacts the limb 103 when the auxiliary pulley 120 rotatesby a predetermined angle so that the auxiliary pulley 120 does notfurther rotate. The stopping pin slot 124 is for adjusting a user'sforce to be applied for shooting an arrow by changing a position wherethe stopping pin 182 is fastened, if necessary. The stopping pin 182consists of a female screw and a male screw to be engaged with eachother so that the user can easily adjust the position where the stoppingpin 182 is fastened.

An interference pin 181 which protrudes toward the main pulley 110 isfastened in the interference pin slot 125 so that the interference pin181 is inserted into a movement hole 116 formed in the main pulley 110.The interference pin 181 rotates with the main pulley 110 and theauxiliary pulley 120 when the bowstring 142 is drawn, and enables themain pulley 110 to rotate with the auxiliary pulley 120 after the mainpulley 110 rotates by a certain angle when the bowstring 142 isreleased. Also, the interference pin slot 125 is for adjusting a user'sforce to be applied for shooting the arrow by changing a position wherethe interference pin 181 is fastened. The interference pin 181 alsoconsists of a female screw and a male screw to be engaged with eachother so that the user can easily adjust the position where theinterference pin 181 is fastened. Moreover, at one end of the guiderecess 122, a fixing protrusion 126 is formed to fix the balance cable141 wound around the guide recess 122. The interference pin 181 and thestopping pin 182 are provided with anti-vibration covers 181 a and 182 arespectively to prevent vibration and noise generated upon contactingother elements.

The main pulley 110 has an approximately circular plate shape and athrough-hole 112 formed at the central region and into which therotation shaft 101 is inserted. The through-hole 112 may beeccentrically formed. The main pulley 110 has a guide recess 111depressed from the outer circumference thereof by a predetermined depthsuch that the balance cable 141 can be wound thereon. And, ananti-vibration guide 172 is installed in the tangential direction of theouter circumference of the main pulley 110 at a position where thebalance cable 141 swerves from the guide recess 111 before the bowstring142 is initially drawn, to guide the balance cable 141. Theanti-vibration guide 172 has a guide recess 172 a into which the balancecable 141 is inserted, which is formed in the middle of theanti-vibration guide 172 in the longitudinal direction. Theanti-vibration guide 172 is made of a rubber material to reducevibration and noise.

The main pulley 110 has an arc-shaped movement hole 116 penetrated tocontrol a moving distance where the interference pin 181 moves. Theinterference pin 181 is supported by one side of the movement hole 116until the stopping pin 182 of the auxiliary pulley 120 contacts thelimbs 103, and enables the main pulley 110 to rotate with the auxiliarypulleys 110. The interference pin 181 is supported by the other side ofthe movement hole 116 and enables the main pulley 110 and the auxiliarypulley 120 to rotate together after the main pulley 110 rotates by acertain angle when the bowstring 142 is released. And, at one end of theguide recess 111, a fixing protrusion 117 is formed to fix the balancecable 141 wound around the guide recess 111.

The cam 130 which is disposed between the main pulley 110 and theauxiliary pulley 120 is fixed to the main pulley 110. A through-hole 112which is formed at the central region of the main pulley 110 isinstalled at one end of the cam 130. The cam 130 has a C-shapedcurvature shape entirely, and includes a gradually curved portion 131having a gradual arc-shape at one side thereof and a steep curvedportion 132 having a steep arc-shape at the other side thereof. Thesteep curved portion 132 is provided with a through-hole 112 and has aradius of curvature smaller than that of the gradually curved portion131, thereby forming a steep slant to become near to the rotation shaft101. The gradually curved portion 131 and the steep curved portion 132have a guide recess 133 around which the cam cable 143 and the bowstring142 are wound. The gradually curved portion 131 includes a fixingprotrusion 115 protruding by a predetermined height from the main pulley110 near to the end of the gradually curved portion 131 to fix the camcable 143, and the steep curved portion 132 includes a fixing protrusion114 protruding by a predetermined height from the main pulley 110 nearto the end of the steep curved portion 132 to fix the bowstring 142.

Meanwhile, the present embodiment has the structure that when thebowstring 142 is drawn for shooting the arrow in a state that thebowstring 142 is wound around the cam 130, the bowstring 142 is releasedfrom the cam 130 and the cam cable 143 is wound around the cam 130. But,as a modification, the bowstring 142 can be wound around a string pulley310, as shown in FIG. 6. An end of the bowstring 142 is coupled to afixing protrusion 317 of the string pulley 310. Here, the balance cableand the bowstring are not shown in FIG. 6 for the sake of convenience.One side of the balance cable is wound around a main pulley 340 and thenis connected to one side of the main pulley 340, and the other side ofthe balance cable is wound around an auxiliary pulley 320 and then isfixed at a fixing protrusion (not shown) which is formed at one side ofthe auxiliary pulley 320. An end of the cam cable is coupled to one sideof the main pulley 340 and is wound around a cam 330 when the bowstringis drawn.

Also, as shown in FIG. 6, an interference pin 381 formed at theauxiliary pulley 320 contacts an interference step 316 formed at oneside of the outer circumference of the main pulley 340, and plays thesame role as that of the above interference pin 181. Then, the mainpulley 340, the cam 330 and the string pulley 310 are coupled androtated together.

And, a stopping pin 382 is formed at a protruded end of a guide recessof the auxiliary pulley 320, and can play the same role as that of theabove stopping pin 182. The auxiliary pulley 120 cannot rotate furtherin the state that the stopping pin 182 contacts the limb, which makesthe balance cable not be released. But, as shown in FIG. 6, the stoppingpin 382 allows the balance cable not to be further released after theauxiliary pulley 320 around which the balance cable is wound rotates bya predetermined angle. Also, the above interference pin 181 and stoppingpin 182 can be identically formed in FIG. 6.

The driven pulley 190 has a circular plate shape and a guide recess 191depressed from the outer circumference by a predetermined depth so thatthe bowstring can be wound thereon. And, an anti-vibration guide 172 isinstalled in the tangential direction of an outer circumference of thedriven pulley 190 at a position where the bowstring 142 swerves from theguide recess 191 before the bowstring 142 is drawn, to guide thebowstring 142. The anti-vibration guide 172 has a guide recess 172 ainto which the bowstring 142 is inserted, which is formed in the middleof the anti-vibration guide 172 in the longitudinal direction. Theanti-vibration guide 172 is made of a rubber material to reducevibration and noise. It is preferable that the guide recess 172 a has awidth narrower than those of the guide recess 111 of the main pulley 110and the guide recess 191 of the driven pulley 190.

Both ends of the balance cable 141 are coupled to the main pulley 110and the auxiliary pulley 120 respectively, and wound around the mainpulley 110 and the auxiliary pulley 120 in the same direction, of whicha middle portion is wound around a balance cable pulley 161 of theconnecting member 360. The balance cable 141 moves from side to sidealong the balance cable pulley 161 according as the bowstring 142 isdrawn for shooting the arrow.

The connecting member 360 includes a housing 162, a connector 162 awhich is formed at an upper portion of the housing 162 and to which oneend of the bowstring 142 is coupled, the balance cable pulley 161 whichis formed at a lower portion of the housing 162 and around which amiddle portion of the balance cable 141 is wound, and a rotation pin 161a which supports the balance cable pulley 161 to be rotated.

Operations of the compound bow according to the first embodiment of thepresent invention will be described as follows.

When the bowstring 142 to which an arrow is notched is drawn back by acertain distance for shooting, the main body 100 is bent inward and thebalance cable 141 allows the main pulley 110 and the auxiliary pulley120 to rotate. And, the interference pin 181 of the auxiliary pulley 120is supported by one end of the movement hole 116 of the main pulley 110or one end of the interference step 316 shown in FIG. 6, and then themain pulley 110 and the auxiliary pulley 120 are rotated together. Sincea released length of the balance cable 141 wound around the auxiliarypulley 120 with a large radius is longer than that of the balance cable141 wound around the main pulley 110, the balance cable pulley 161 isdriven to compensate a difference between the released lengths. In otherwords, the balance cable 141 passes through the balance cable pulley 161and moves toward the main pulley 110.

As described above, since the drawing force of the bowstring 142 isdivided and applied to the main pulley 110 and the auxiliary pulley 120when the bowstring 142 is early drawn back, the bowstring 142 can bedrawn even with a weak force due to the auxiliary pulley 120 with alarge radius.

The auxiliary pulley 120 rotating together with the main pulley 110 doesnot rotate further after the stopping pin 182 installed to the auxiliarypulley 120 contacts the limb 103.

When the bowstring 142 is drawn further, the rotating cam 130 is in alet-off state. In other words, the bowstring 142 wound around the cam130 passes through the gradually curved portion 131 and is positioned atthe steep curved portion 132 so that the drawing force is rapidlyreduced. Since the auxiliary pulley 120 cannot rotate further in a statethat the stopping pin 182 contacts the limb 103, only the main pulley110 rotates. When the main pulley 110 only rotates, the interference pin181 supported by one side of the movement hole 116 is released. In FIG.6, the interference pin 381 supported by the interference step 316 isreleased.

In this state, when the bowstring 142 is drawn back by maximum and thenis released in a fully drawn state, the bowstring 142 is returned to theoriginal state due to the resilient force of the main body 100 itselfand the arrow is shot. At this time, a force is applied to the mainpulley 110 and the balance cable 141 is drawn with a large force, sothat a propulsive force of the arrow can be increased.

When the interference pin 181 again contacts one end of the movementhole 116 formed in the main pulley 110 rotating alone, the auxiliarypulley 120 rotates together with the main pulley 110 until the bowstring142 is returned to the original state.

As described above, according to the compound bow of the firstembodiment of the present invention, since a force is divided andapplied to the main pulley 110 and the auxiliary pulley with a radiusgreater than that of the main pulley 110 when drawing the bowstring 142,a force required to draw the bowstring 142 is reduced.

When the bowstring 142 starts to return to the original state from astate of fully drawing the bowstring 142, a force is applied to the mainpulley 110, and then the propulsive force of shooting the arrow isincreased.

Next, the compound bow according to the second embodiment of the presentinvention will be described as follows.

FIG. 8 is an exploded perspective view illustrating a stopper member ofa compound bow according to a second embodiment of the presentinvention, FIGS. 9 to 12 are schematic views subsequently illustratingoperating states of the stopper member when the compound bow isoperated, in which FIG. 9 illustrates a state of the stopper memberbefore the bowstring is drawn, FIG. 10 illustrates a state of thestopper member when the bowstring is drawn by a predetermined distance,and FIG. 11 illustrates a state of the stopper member before an arrow isshot, and FIG. 12 illustrates a state of the stopper member after anarrow is shot.

As illustrated, a compound bow according to the second embodiment of thepresent invention includes a main body 100 having a handle 102 graspedby a user, rotation shafts 101 installed to both ends of the main body100; a dual pulley including a main pulley 110 installed to rotatearound the rotation shaft 101 that is installed to one end of the mainbody 100 and an auxiliary pulley 120 having a radius greater than thatof the main pulley 110 and rotatably installed around the rotation shaft101; a cam 130 positioned between the main pulley 110 and the auxiliarypulley 120 and installed to the main pulley 110; a balance cable 141having ends fixed to the main pulley 110 and the auxiliary pulley 120and wound around the main pulley 110 and the auxiliary pulley 120 in thesame direction; a stopper member 260 for temporally fixing the balancecable 141, including a balance cable pulley 161 which is installed atone end thereof and around which a central portion of the balance cable141 is wound; a cam cable 130 having one end fixed to the other end ofthe main body and the other end fixed to the main pulley, and beingwound around the cam in the opposite direction to that of the balancecable; a driven pulley 190 rotatably installed on the rotation shaft 101that is installed at an other end of the main body 100; and a bowstring142 having one end coupled to the stopper member 260 and being woundaround the driven pulley 190, and the other end fixed to the main pulley110 and being wound around the cam 130 in the direction opposite to thecam cable 143.

Since the pulleys and cam of the compound bow according to the secondembodiment of the present invention are the same as those of the firstembodiment, the detailed description thereof will be omittedhereinafter. But, the second embodiment includes that a stopper member260 is formed instead of the connecting member 360, and the balancecable 141 has a different construction from that of the firstembodiment.

Both ends of the balance cable 141 are coupled to the main pulley 110and the auxiliary pulley 120 respectively, and wound around the mainpulley 110 and the auxiliary pulley 120 in the same direction, of whicha middle portion is wound around a balance cable pulley 161 of thestopper member 260. Also, at one side of the balance cable 141 near tothe main pulley 110 from the balance cable pulley 161, a clip 141 a of acylindrical shape having a diameter larger than that of the balancecable 141 is fastened. The balance cable 141 moves from side to sidealong the balance cable pulley 161 according as the bowstring 142 isdrawn for shooting the arrow.

The stopper member 260 is for temporally fixing the balance cable 141when the arrow is shot, and includes the balance cable pulley 161, astopper 165, a trigger 166, and a housing 162 for holding theseelements.

The housing 162 includes a connector 162 a which is formed at the upperportion thereof and to which the bowstring 142 is coupled, a rotationpin 161 a which is formed at one side of the central portion thereof andsupports a balance cable pulley 161 to be rotated, and a rotation pin166 a which is formed at the other side of the central portion thereofand supports the trigger 166 to be rotated.

Also, at one side of the lower portion of the housing 162, a rotationpin 165 a is formed below the rotation pin 166 a to support the stopper165 rotatably. And, at the other side of the lower portion of thehousing 162, a rest portion 162 d having a rest groove 162 c in which acontact 166 c of the trigger 166 is secured is formed.

The stopper 165 is connected to the rotation pin 165 a at the centerthereof, of which the right side is in a semicircular shape, and at theleft upper side of which a pushing section 165 e protruded to the leftside is formed to contact an upper end of the clip 141 a, and at theleft lower side of which a locking hook 165 b is spaced from the pushingsection 165 e at a predetermined distance and temporarily supports alower end of the clip 141 a. And, a movement recess 165 c isrespectively depressed from each of the left ends of the pushing section165 e and the locking hook 165 b by a predetermined distance. Thebalance cable 141 is inserted into the movement recess 165 c and canmoves up and down. Also, a locker 165 f of a stepped shape is formed atthe upper outer circumference of the stopper 165 so that a locking step166 b of the trigger 166 is caught. Also, the stopper 165 includes asupport 165 d, of which one end is engaged with the stopper 165 torotate the trigger 166 so that the locking step 166 b is caught to thelocker 165 f when the stopper 165 rotates, and of which the other sidebeing wound around the rotation pin 165 a twice or three times isprotruded and formed to contact the other side of the trigger 166. Thesupport 165 d is preferably made of spring.

The trigger 166 for preventing the rotation of the stopper 165 when theclip 141 a is positioned between the pushing section 165 e and thelocking hook 165 b of the stopper 165 before the arrow is shot. One sideof the trigger 166 is rotatably connected to a rotation pin 166 a, andthe other side thereof extends toward the balance cable 141 which isnear to the auxiliary pulley 120 from the balance cable pulley 161.Also, one side of the trigger 166 to which the rotation pin 166 a isconnected has a cylindrical shape with a cut side such that a lockingstep 166 b by which the locker 165 f is temporally supported can beformed. At the other side end of the trigger 166, a contact 166 c isformed to contact the balance cable 141.

Operations of the compound bow according to the second embodiment of thepresent invention will be described as follows.

As illustrated in FIG. 9, before drawing the bowstring 142, the lockingstep 166 b of the trigger 166 is separated from the locker 165 f of thestopper 165. Therefore, at this state, when the bowstring 142 is drawnback by a certain distance, the main body 100, is bent inward and thebalance cable 141 allows the main pulley 110 and the auxiliary pulley120 to rotate. And, the interference pin 181 of the auxiliary pulley 120is supported by one end of the movement hole 116 of the main pulley 110,and then the main pulley 110 and the auxiliary pulley 120 are rotatedtogether. Since a released length of the balance cable 141 wound aroundthe auxiliary pulley 120 with a large radius is longer than that of thebalance cable 141 wound around the main pulley 110, the balance cablepulley 161 is driven to compensate a difference between the releasedlengths. In other words, the balance cable 141 passes through thebalance cable pulley 161 and moves toward the main pulley 110. Asdescribed above, during the movement of the balance cable 141 toward themain pulley 110, the clip 141 a moves downward the stopper member 260,as illustrated in FIG. 10, whereby the clip 141 a pushes the lockinghook 165 b and the stopper 165 rotates by a predetermined anglecounterclockwise. At this time, a difference between the auxiliarypulley 120 and the main pulley 110 in size causes the balance cable 141to get broad about the balance cable pulley 161.

As described above, since the drawing force of the bowstring 142 isdivided and applied to the main pulley 110 and the auxiliary pulley 120when the bowstring 142 is early drawn back, the bowstring 142 can bedrawn even with a weak force due to the auxiliary pulley 120 with alarge radius.

The auxiliary pulley 120 rotating together with the main pulley 110 doesnot rotate further after the stopping pin 182 installed to the auxiliarypulley 120 contacts the limb 103.

When the bowstring 142 is drawn further, the rotating cam 130 is in alet-off state. In other words, the bowstring 142 wound around the cam130 passes through the gradually curved portion 131 and is positioned atthe steep curved portion 132 so that the drawing force is rapidlyreduced. Since the auxiliary pulley 120 cannot rotate further in a statethat the stopping pin 182 contacts the limb 103, only the main pulley110 rotates. When the main pulley 110 only rotates, the interference pin181 supported by one side of the movement hole 116 is released and theclip 141 a gradually approaches to the stopper 165 again.

In this state, when the bowstring 142 is drawn back by maximum toachieve a state as illustrated in FIG. 11, the clip 141 a pushes thepushing section 165 e of the stopper 165 and rotates the stopper 165 bya predetermined angle clockwise. When the stopper 165 rotates, thesupport 165 d which contacts the other side of the trigger 166 rotatesthe trigger 166, and the locking step 166 b is positioned so that thelocker 165 f of the stopper 165 is caught thereto.

Next, when the bowstring 142 is released in a fully drawn state, asshown in FIG. 12, the locker 165 f of the stopper 165 is caught to thelocking step 166 b of the trigger 166 to thereby make the stopper 165not rotate, and thus a lower end of the clip 141 a is fastened by thelocking hook 165 b of the stopper 165.

Like this, when the bowstring 142 is released in the state that the clip141 a is locked by the locking hook 165 b of the stopper 165, thebowstring 142 is returned to the original state due to the resilientforce of the main body 100 itself and an arrow is shot. At this time, aforce is applied to the main pulley 110 and the balance cable 141 isdrawn with a large force, so that the balance cable 141 is wound aroundonly the main pulley 110.

In this case, since the force is not applied to the auxiliary pulley120, the balance cable 141 wound around the auxiliary pulley 120 isrelatively loose. But, the separation preventing unit 127 of theauxiliary pulley 120 is protruded from the guide recess 122 and thebalance cable 141 is placed in the separation preventing unit 127.

When the interference pin 181 again contacts one end of the movementhole 116 formed in the main pulley 110 rotating alone, the auxiliarypulley 120 rotates together with the main pulley 110 until the bowstring142 is returned to the original state.

Then, since the balance cable 141 is again wound around the main pulley110 and the auxiliary pulley 120, the balance cable 141 is in a parallelstate around the balance cable pulley 161, as shown in FIG. 9. And, thebalance cable 141 near to the auxiliary pulley 120 from the balancecable pulley 161 slides on the contact 166 c of the trigger 166, andmakes the trigger 166 rotate counterclockwise. The locking step 166 b isseparated from the locker 165 f of the stopper 165 according as thetrigger 166 rotates counterclockwise.

As described above, according to the compound bow of the secondembodiment of the present invention, since a force is divided andapplied to the main pulley 110 and the auxiliary pulley with a radiusgreater than that of the main pulley 110 when drawing the bowstring 142,a force required to draw the bowstring 142 is reduced.

When the bowstring 142 starts to return to the original state from astate of fully drawing the bowstring 142, a force is applied to the mainpulley 110 because of the coupled state of the clip 141 a by the lockinghook 165 b of the stopper, so that the bowstring 142 is wound with alarge force and the propulsive force of shooting the arrow is increased,which is larger than the propulsive force done in the first embodiment.

Hereinafter, a compound bow according to a third embodiment of thepresent invention will be described in detail with reference to theaccompanying drawings as follows.

FIG. 13 is a perspective view illustrating a compound bow according to athird embodiment of the present invention, FIG. 14 is an explodedperspective view of a stopper member illustrated in FIG. 13, and FIGS.15 to 17 are schematic views illustrating operating states of thecompound bow according to the third embodiment of the present invention,in which FIG. 15 illustrates a state before the bowstring is drawnaccording to the third embodiment of the present invention, FIG. 16illustrates a state that the bowstring is drawn by a predetermineddistance according to the third embodiment of the present invention, andFIG. 17 illustrates a state the bowstring is fully drawn according tothe third embodiment of the present invention.

Differences between the compound bow according to the third embodimentof the present invention and that of the second embodiment will bedescribed as follows. Instead of the clip 141 a which is coupled to thebalance cable 141 in the second embodiment, a fixed plate 150 with alocking ring 151 is connected to the balance cable 141, and theconstruction of the stopper member 160 is different from that of astopper member 260 in the first embodiment. The fixing plate 150 isformed with a coupling hole 152 penetrating the fixing plate 150 in alongitudinal direction, into which the balance cable 141 is inserted andfixed.

In the embodiment, the stopper member 160, as shown in FIG. 14, includesa housing 162 having a connector 162 a formed at one side thereof and towhich the bowstring 142 is connected, a rotation pin 161 a formed at thecentral portion thereof and supporting a balance cable pulley 161 to berotated, and a protrusion 162 b protruding from the other end of thehousing 162 by a predetermined length, a latch 163 rotatably installedon the rotation pin 163 d fixed to the end of the protrusion 162 b, afirst torsion spring 163 c pressing the latch 163 to rotate in adirection, a detent 164 rotatably installed on the rotation pin 164 dfixed to the central portion of the protrusion 162 b, and a secondtorsion spring 164 c pressing the detent 164 to rotate in a direction.

The latch 163 has a circular ring shape and a locking hook 163 a bentand protruding from one side to temporally fix the locking ring 151. Thelatch 163 includes a locker 163 b protruded from the other side thereofand controlling a rotation. The first torsion spring 163 c presses thelocking hook 163 a in the direction that the locking hook 163 a iscoupled with the locking ring 151.

The detent 164 has a circular ring shape with a cut side such that alocking step 164 a by which the locker 163 b is temporally supported canbe formed at one side. The detent 164 includes a knob pin 164 dprotruding from the other side thereof toward the outside of the housing162. The second torsion spring 164 c presses the detent 164 in thedirection where a state of the locker 163 b being locked by the lockingstep 164 a is maintained.

The knob pin 164 b may be driven manually by a user or automatically bywhich one end of the knob pin 164 b is connected to one side of the camcable 143 by a release wire (not shown) and the drawn bowstring 142 isreturned to the original state. In this case, a position on the camcable 143 to which the release wire is connected is fixed between aposition where the release wire contacts the stopper member 160 and aposition of the cam 130 to which the release wire is fixed.

Since other constructions are the same as those of the secondembodiment, the detailed description thereof will be omitted.

Operations of the compound bow according to the third embodiment of thepresent invention will be described as follows.

As illustrated in FIG. 15, before drawing the bowstring 142, the knobpin 164 b of the stopper member 160 is pressed to release the lockedstate of the locker 163 b locked by the locking step 164 a and the latch164 rotates such that the locking ring 151 inserted into the lockinghook 163 a is separated, and then the stopper member 160 and the lockingring 151 are separated from each other.

In this state, when the bowstring 142 is drawn by a distance, the mainbody 100, as illustrated in FIG. 16, is bent inward, and the balancecable 141 have the main pulley 110 and the auxiliary pulley 120 rotated.At this time, while the balance cable 141 moves toward the main pulley110, a distance between the stopper member 160 and the locking ring 151becomes farther. Until this state, the interference pin 181 is stillsupported by one side of the movement hole 116.

The auxiliary pulley 120 rotating together with the main pulley 110 doesnot rotate further after the stopping pin 182 mounted to the auxiliarypulley 120 contacts the limb 103, and only the main pulley 110 rotates.When the main pulley 110 only rotates, the interference pin 181supported by one side of the movement hole 116 is released, and thelocking ring 151 gradually approaches to the stopper member 160 again.

In this state, when the bowstring 142 is drawn by maximum to achieve astate as illustrated in FIG. 17, the locking ring 151 contacts thelocking hook 163 a and is temporally coupled therewith. A contactsurface of the locking hook 163 a that the locking ring 151 contactsforms a slope such that the locking ring 151 is easily inserted into thelocking hook 163 a.

Then, when the bowstring 142 is released in the state of fully drawingthe bowstring 142, the bowstring 142 is returned to the original statedue to the resilient force of the main body 100 and the arrow is shot.

As described above, when the bowstring 142 is released at the state thatthe locking ring 151 is locked by the locking hook 163 a, a force isconcentrated to the main pulley 110 and the balance cable 141 is drawnwith a large force so that the balance cable 141 is wound around onlythe main pulley 110.

When the bowstring 142 is returned to the original state, the arrow isshot and the locking ring 151 still maintains the locked state in thelocking hook 163 a.

Next, when the user presses the knob pin 164 a and releases the lockingring 151 from the locking hook 163 a before the shooting, it is possibleto shoot the next arrow. Other operations and effect are the same asthose of the second embodiment.

Hereinafter, a compound bow according to a fourth embodiment of thepresent invention will be described in detail with reference to theaccompanying drawings as follows.

FIG. 18 is a perspective view illustrating a compound bow according to afourth embodiment of the present invention, FIGS. 19 and 20 are explodedperspective views illustrating a main pulley, an auxiliary pulley, and acam as shown in FIG. 18, and FIGS. 21 to 23 are schematic viewsillustrating operating states of the compound bow according to thefourth embodiment of the present invention, in which FIG. 21 illustratesa state before the bowstring is drawn, FIG. 22 illustrates a state thatthe bowstring is drawn by a predetermined distance, and FIG. 23 is aview illustrating a state that the bowstring is fully drawn.

As illustrated, the compound bow according to the fourth embodiment ofthe present invention includes a main body 100 having a handle 102grasped by a user and a pair of limbs 103 coupled to both ends of thehandle 102 and having two branches at the rear ends thereof, rotationshafts 101 respectively installed to both ends of the main body 100,that is, ends of the limbs 103, dual pulleys including a main pulleys210 installed to rotate around the rotation shafts 101 and auxiliarypulleys 220 having a radius greater than those of the main pulleys 210and installed to rotate around the rotation shafts 101, which arerespectively installed on the rotation shafts 101 of both ends of themain body 100, cams 230 disposed between the main pulleys 210 and theauxiliary pulleys 220 and installed to the main pulleys 210, stoppingpins 282 installed to the auxiliary pulleys 220 to protrude toward thelimbs 103, balance cables 241 having both ends fixed to the main pulleys210 and the auxiliary pulleys 220 and wound around the main pulleys 210and the auxiliary pulleys 220 in the same direction, locking rings 151respectively installed on the central portions of the balance cables 241near to the main pulleys 210, stopper members 160 positioned at thecentral portions of the balance cables 241 and to which the lockingrings 151 are temporally fixed, cam cables 243, each respectively havingone end coupled to any one of both ends of the main body 100 and theother end thereof fixed to the main pulley 210 installed at the rotationshaft 101 which fixed to the other end of the main body 100, and woundaround the cam 230 in the direction opposite to that of the balancecables 241, and a bowstring 242 of which both ends are connected to thestopper members 160, respectively.

Configurations of the stopper members 160 and the locking rings 151 areidentical to those of the third embodiment and their detaileddescription will be omitted.

Each of the auxiliary pulleys 220 has an approximately oval plate shapeand has an eccentric through-hole 221 formed at the central regionthereof. The auxiliary pulley 220 has a guide recess 222 formed on theouter circumference thereof by a predetermined depth and a predeterminedlength such that the balance cable 241 can be wound around the outercircumference thereof. A separation preventing unit 227 protrudes fromone side of the guide recess 222 by a predetermined height along theguide recess 222 and prevents separation of the balance cable 241. Anarc-shaped stopping pin slot 224 and an arc-shaped interference pin slot225 are formed about the through-hole 221. A stopping pin 282 whichprotrudes by a predetermined height and temporally contacts the limb 103is screwed in the stopping pin slot 224. An interference pin 281protruding toward the main pulley 210 is screwed in the interference pinslot 225. Since the stopping pin 282 and the interference pin 281 arescrewed, it is possible to adjust positions of the pins 282 and 281 tosatisfy user's favorites, and their functions are identical with thoseof the above embodiments. At one end of the guide recess 222, a fixingprotrusion 226 is formed to fix the balance cable 241 wound around theguide recess 222.

Each of the main pulleys 210 has an approximately circular plate shapeand a through-hole 212 formed at the central region thereof and intowhich the rotation shaft 101 is inserted. The through-hole 212 may beeccentrically formed. The main pulley 210 has a guide recess 211depressed from the outer circumference thereof by a predetermined depthsuch that the balance cable 241 can be wound. The main pulley 210 has aninterference step 216 protruding from a predetermined portion of theouter circumference thereof such that the interference pin 281 cantemporally contact.

Differently from the first embodiment, the present embodiment describesthat the main pulley 210 has the interference step 216 with which theinterference pin 281 contacts. But, the movement hole 116 into which theinterference pin is inserted may be formed as in the first embodiment.At one end of the guide recess 211, a fixing protrusion 217 is formed tofix the balance cable 241 wound around the guide recess 211.

Each of the cams 230 disposed between the main pulleys 210 and theauxiliary pulleys 220 is fixed to the main pulley 210. The cam 230 hasan approximately fan plate shape, and includes a gradually curvedportion 231 having a gradual arc-shape and a steep curved portion 232connected to the end of the gradually curved portion 231 and having asteep arc-shape so that the other end thereof is near to the rotationshaft 101. The gradually curved portion 231 and the steep curved portion232 have a guide recess 233 depressed by a predetermined depth to guidethe cam cables 243. As illustrated, it is also preferable that anothergradually curved portion having the same shape as that of the graduallycurved portions 231 extends to a side of the main pulley 210. At theends of the gradually curved portions 231 or the extending graduallycurved portions, fixing protrusions 214 protrude from the main pulleys210 by a predetermined height to fix the cam cables 243 wound around thecams 230.

Although not illustrated, it is preferable that anti-vibration guides172 (not shown) are installed to the main pulleys 210 like theabove-mentioned embodiments of the present invention.

Anti-vibration covers 281 a and 282 a are provided for covering on theinterference pins 281 and the stopping pins 282 in order to reducevibration and noise.

Operations of the compound bow according to the fourth embodiment of thepresent invention will be briefly described as follows.

As illustrated in FIG. 21, before drawing the bowstring 242, the knobpins 164 b of the stopper members 160 are pressed to separate thelocking rings 151 inserted into the locking hooks 163 a such that thestopper members 160 and the locking rings 151 are separated from eachother. The stopper members 160 respectively formed at both ends of thebowstring 242 must be separated from the locking rings 151.

In this state, when the bowstring 242 is drawn by a distance, the mainbody 100, as illustrated in FIG. 22, is bent and the balance cables 241have the main pulleys 210 and the auxiliary pulleys 220 rotated. At thistime, the balance cable pulleys 161 are driven to compensate adifference between the released lengths of the balance cables 243released from the main pulleys 210 and the auxiliary pulleys 220. Inother words, during the movement of the balance cables 241 toward themain pulleys 210, a distance between the stopper members 160 and thelocking rings 151 becomes farther. Until this state, the interferencepins 281 are still supported by the interference steps 216.

As described above, since the drawing force of the bowstring 242 isdivided and applied to the main pulleys 210 and the auxiliary pulleys220 when the bowstring 242 are early drawn, the bowstring 242 can bedrawn even with a weak force due to the auxiliary pulleys 220 with alarge radius.

The auxiliary pulleys 220 rotating together with the main pulleys 210 donot rotate further after the stopping pins 282 installed to theauxiliary pulleys 220 contact the limbs 103.

When the bowstring 242 is drawn further, the rotating cams 230 are in alet-off state. In other words, the cam cables 243 wound around the cams230 passes through the gradually curved portions 231 and are positionedat the steep curved portions 232 so that the drawing force is rapidlyreduced. Since the auxiliary pulleys 220 cannot rotate further in astate that the stopping pins 282 contact the limbs 103, only the mainpulleys 210 rotate. When the main pulleys 210 only rotate, theinterference pins 281 contacting the interference steps 216 are releasedfrom the supported state, and the locking rings 151 gradually approachto the stopper members 160 again.

In this state, when the bowstring 242 is drawn by maximum to achieve astate as illustrated in FIG. 23, the respective locking rings 151 aretemporally locked by the locking hooks 163 a.

When the bowstring 242 is released in the state of fully drawing thebowstring 242, the bowstring 242 is returned to the original state dueto the resilient force of the main body 100 and an arrow is shot.

As described above, when the bowstring 242 is released at the state thatthe locking rings 151 are engaged with the locking hooks 163 a, a forceis concentrated to the main pulleys 210 and the balance cables 241 aredrawn with a large force so that the balance cables 241 are wound aroundonly the main pulleys 210.

Next, when the main pulleys 210 rotate by a predetermined angle, theinterference steps 216 which are formed at the main pulleys 210 rotatingalone contact the interference pins 281, and the auxiliary pulleys 220rotate together with the main pulleys 210 until the bowstring 242 isreturned to the original state.

As described above, according to the compound bow of the fourthembodiment of the present invention, since a force is divided andapplied to the main pulleys 210 and the auxiliary pulleys 220 whendrawing the bowstring 242, like in the above-mentioned embodiments ofthe present invention, a force required to draw the bowstring 242 isreduced.

And, since the stopper members 160 are provided at both ends of thebowstring 242, the propulsive force of shooting the arrow is doubled.

Next, the compound bow according to a fifth embodiment of the presentinvention will be described with reference to FIG. 24. FIG. 24 is aperspective view illustrating a compound bow according to the fifthembodiment of the present invention. Differences between the fifthembodiment and the fourth embodiment of the present invention are thatthe stopper members 160 of the compound bow in the fourth embodiment areidentical with that of the third embodiment, but the compound bow in thefifth embodiment adopts the stopper member 260 of the second embodiment.

The operations of the main pulleys, auxiliary pulleys and cams coupledto the main body in the fifth embodiment are identical with those of thefourth embodiment, and the operations of the stopper members 260 areidentical with that of the second embodiment and the effect of the fifthembodiment is the same as that of the fourth embodiment.

That is, according to the compound bow of the fifth embodiment of thepresent invention, since a force is divided and applied to the mainpulleys 210 and the auxiliary pulleys 220 when drawing the bowstring242, like in the above-mentioned embodiments of the present invention, aforce required to draw the bowstring 242 is reduced.

And, since the stopper members 260 are provided at both ends of thebowstring 242, the propulsive force of shooting an arrow is doubled.

Also, as still other embodiment, the compound bow of the fourthembodiment can adopt the connecting member 360 of the first embodimentinstead of the stopper member 160. In this case, the operations andeffect of the connecting member are the same as those of the firstembodiment.

As described above, the compound bow according to the present inventionprovides an effect of improving the efficiency of the compound bow byreducing the force required to draw a bowstring and increasing thepropulsive force of shooting the arrow.

Although exemplary embodiments of the present invention have beendescribed in detail hereinabove, it should be understood that manyvariations and modifications of the basic inventive concept hereindescribed, which may appear to those skilled in the art, will still fallwithin the spirit and scope of the exemplary embodiments of the presentinvention as defined in the appended claims.

1. A compound bow comprising: a main body having a handle grasped by auser and a pair of limbs coupled to both ends of the handle; a dualpulley including a main pulley installed to rotate around a rotationshaft which is installed to one end of the main body and an auxiliarypulley having a radius greater than that of the main pulley androtatably installed around the rotation shaft; a driven pulley rotatablyinstalled on the rotation shaft which is installed at the other end ofthe main body; a cam installed to the main pulley; a balance cablehaving both ends respectively connected to the main pulley and theauxiliary pulley, and wound around the main pulley and the auxiliarypulley in the same direction; a connecting member including a balancecable pulley around which a middle portion of the balance cable is woundand which is positioned at a lower side thereof; a bowstring having oneend coupled to an upper portion of the connecting member, a middleportion wound around the driven pulley and the other end connected tothe main pulley, and being wound around the cam; and a cam cable havingone end connected to the other end of the main body and the other endconnected to the main pulley, and being wound around the cam when thebowstring is drawn for shooting an arrow.
 2. The compound bow accordingto claim 1, wherein the auxiliary pulley further comprises a stoppingpin which is installed to the auxiliary pulley and temporally contactsthe main body when the auxiliary pulley rotates by a predetermined anglesuch that the auxiliary pulley does not rotate further.
 3. The compoundbow according to claim 2, wherein the auxiliary pulley further includesan interference pin which moves along an movement hole formed in themain pulley.
 4. A compound bow comprising: a main body having a handlegrasped by a user and a pair of limbs coupled to both ends of thehandle; a dual pulley including a main pulley installed to rotate arounda rotation shaft which is installed to one end of the main body and anauxiliary pulley having a radius greater than that of the main pulleyand rotatably installed around the rotation shaft; a driven pulleyrotatably installed on the rotation shaft which is installed at theother end of the main body; a cam installed to the main pulley; a stringpulley installed to rotate around the rotation shaft which is installedto one end of the main body and coupled with the main pulley; a balancecable having both ends respectively connected to the main pulley and theauxiliary pulley, and wound around the main pulley and the auxiliarypulley in the same direction; a connecting member including a balancecable pulley around which a middle portion of the balance cable is woundand which is positioned at a lower side thereof; a bowstring having oneend coupled to an upper portion of the connecting member, a middleportion wound around the driven pulley and the other end connected tothe string pulley, and being wound around the string pulley; and a camcable having one end connected to the other end of the main body and theother end connected to the main pulley, and being wound around the camwhen the bowstring is drawn for shooting an arrow.
 5. The compound bowaccording to claim 4, wherein the auxiliary pulley further comprises astopping pin which is installed to the auxiliary pulley and temporallycontacts the main body when the auxiliary pulley rotates by apredetermined angle such that the auxiliary pulley does not rotatefurther.
 6. The compound bow according to claim 5, wherein the auxiliarypulley further includes an interference pin which contacts aninterference step formed at one side of the outer circumference of themain pulley.
 7. A compound bow comprising: a main body having a handlegrasped by a user, and a pair of limbs coupled to both ends of thehandle; rotation shafts fixed to both ends of the main body,respectively; dual pulleys, each including a main pulley rotatablyinstalled on the rotation shaft fixed to one end of the main body, andan auxiliary pulley having a radius greater than that of the main pulleyand rotatably installed on the rotation shaft; cams, each installed tothe main pulley; balance cables, both ends of which are connected to themain pulley and the auxiliary pulley and wound around the main pulleyand the auxiliary pulley in the same direction; connecting members, eachincluding a balance cable pulley around which a middle portion of thebalance cable is wound and which is positioned at one side thereof; abowstring, of which both ends are connected to the connecting members;and cam cables, each having one end which is connected to any one ofboth ends of the main body and the other end which is connected to themain pulley which is formed at the rotation shaft installed to the otherend of the main body, and being wound around the cam when the bowstringis drawn for shooting an arrow.
 8. The compound bow according to claim7, wherein the auxiliary pulley further comprises a stopping pin whichis installed to the auxiliary pulley and temporally contacts the mainbody when the auxiliary pulley rotates by a predetermined angle suchthat the auxiliary pulley does not rotate further.
 9. The compound bowaccording to claim 8, wherein the auxiliary pulley further includes aninterference pin which moves along an movement hole formed in the mainpulley.
 10. The compound bow according to claim 8, wherein the auxiliarypulley further includes an interference pin which contacts aninterference step formed in the main pulley.
 11. A compound bowcomprising: a main body having a handle grasped by a user and a pair oflimbs coupled to both ends of the handle; a dual pulley including a mainpulley installed to rotate around a rotation shaft which is installed toone end of the main body and an auxiliary pulley having a radius greaterthan that of the main pulley and rotatably installed around the rotationshaft; a driven pulley rotatably installed on the rotation shaft whichis installed at the other end of the main body; a cam installed to themain pulley; a string pulley installed to rotate around the rotationshaft which is installed to one end of the main body and coupled withthe main pulley; a balance cable having both ends respectively connectedto the main pulley and the auxiliary pulley, and wound around the mainpulley and the auxiliary pulley in the same direction; a stopper memberincluding a balance cable pulley around which a middle portion of thebalance cable is wound and which is positioned at a lower side thereof,and temporarily fixing the balance cable when an arrow is shot; abowstring having one end coupled to an upper portion of the stoppermember, a middle portion wound around the driven pulley and the otherend connected to the string pulley, and being wound around the stringpulley; and a cam cable having one end connected to the other end of themain body and the other end connected to the main pulley, and beingwound around the cam when the bowstring is drawn for shooting an arrow.12. The compound bow according to claim 11, wherein the stopper memberincludes a housing, to an upper portion of which one end of thebowstring is coupled and to one side of a central portion of which thebalance cable pulley is rotatably installed; and a stopper, formed at alower side of the housing, including a locking hook by which a clip iscaught to be temporarily fixed, wherein the clip is mounted at one sideof the balance cable near to the main pulley from the balance cablepulley.
 13. The compound bow according to claim 12, wherein the stopperis rotatably coupled to the housing, and further includes a locker of astepped shape so that the clip is fastened by the locking hook byrestricting the rotation of the stopper when the arrow is shot; and thestopper member further includes a trigger having a locking step which isformed at one end thereof and temporarily contacts the locker of thestopper to control the rotation of the stopper.
 14. The compound bowaccording to claim 13, wherein the trigger having the locking stepformed at one end thereof is rotatably coupled to the housing; and thestopper further includes a pushing section which is spaced at apredetermined distance from and protrudes from the locking hook so thatan upper portion of the clip contacts the stopper for its rotation whenthe clip moves into the housing; and a support, of which one end isengaged with the stopper, and of which the other end contacts the otherside of the trigger to rotate the trigger according to the rotation ofthe stopper and makes the locking step be caught to the locker.
 15. Thecompound bow according to claim 14, wherein the trigger further includesa contact which is formed at the other end thereof and contacts thebalance cable near to the auxiliary pulley from the balance cablepulley, by which the balance cable rotates the trigger to have thelocking step be separated from the locker when the balance cable isrewound around the main pulley and the auxiliary pulley after the arrowis shot.
 16. The compound bow according to claim 11, wherein theauxiliary pulley further comprises a stopping pin which is installed tothe auxiliary pulley and temporally contacts the main body when theauxiliary pulley rotates by a predetermined angle such that theauxiliary pulley does not rotate further.
 17. The compound bow accordingto claim 16, wherein the stopping pin is in a screw-coupled fashion andis fastened to a predetermined portion of a stopping pin slot formed inthe auxiliary pulley.
 18. The compound bow according to claim 16,wherein the stopping pin are covered with anti-vibration coverspreventing noise and vibration.
 19. The compound bow according to claim16, wherein the auxiliary pulley further includes an interference pinwhich moves along an movement hole formed in the main pulley.
 20. Thecompound bow according to claim 16, wherein the auxiliary pulley furtherincludes an interference pin which contacts an interference step formedin the main pulley.
 21. The compound bow according to claim 19, whereinthe interference pin is in a screw-coupled fashion and is fastened to apredetermined portion of an interference pin slot formed in theauxiliary pulley.
 22. The compound bow according to claim 19, whereinthe interference pin are covered with anti-vibration covers preventingnoise and vibration.
 23. The compound bow according to claim 16, whereinthe stopper member includes a housing, to an upper portion of which oneend of the bowstring is coupled and to one side of a central portion ofwhich the balance cable pulley is rotatably installed; and a stopper,formed at a lower side of the housing, including a locking hook by whicha clip is caught to be temporarily fixed, wherein the clip is mounted atone side of the balance cable near to the main pulley from the balancecable pulley.
 24. The compound bow according to claim 23, wherein thestopper is rotatably coupled to the housing, and further includes alocker of a stepped shape so that the clip is fastened by the lockinghook by restricting the rotation of the stopper when the arrow is shot;and the stopper member further includes a trigger having a locking stepwhich is formed at one end thereof and temporarily contacts the lockerof the stopper to control the rotation of the stopper.
 25. The compoundbow according to claim 24, wherein the trigger having the locking stepformed at one end thereof is rotatably coupled to the housing; and thestopper further includes a pushing section which is spaced at apredetermined distance from and protrudes from the locking hook so thatan upper portion of the clip contacts the stopper for its rotation whenthe clip moves into the housing; and a support, of which one end isengaged with the stopper, and of which the other end contacts the otherside of the trigger to rotate the trigger according to the rotation ofthe stopper and makes the locking step be caught to the locker.
 26. Thecompound bow according to claim 25, wherein the trigger further includesa contact which is formed at the other end thereof and contacts thebalance cable near to the auxiliary pulley from the balance cablepulley, by which the balance cable rotates the trigger to have thelocking step be separated from the locker when the balance cable isrewound around the main pulley and the auxiliary pulley after the arrowis shot.
 27. The compound bow according to claim 25, wherein theauxiliary pulley further includes an interference pin which moves alongan movement hole formed in the main pulley.
 28. The compound bowaccording to claim 11, wherein the main pulley and the auxiliary pulleyare eccentrically installed on the rotation shaft.
 29. The compound bowaccording to claim 11, wherein each of the main pulley, the auxiliarypulley, and the driven pulley includes a guide recess, depressed fromthe outer circumference thereof, around which the balance cable or thebowstring are wound; and the auxiliary pulley includes a separationpreventing unit protruding along the guide recess by a predeterminedheight to prevent separation of the balance cable.
 30. The compound bowaccording to claim 11, wherein the main pulley further comprises ananti-vibration guide which is formed at one side of the outercircumference thereof and has a guide recess installed in the tangentialdirection of the outer circumference thereof.
 31. The compound bowaccording to claim 11, wherein the cam includes: a gradually curvedportion with an arc-shape; a steep curved portion connected to one endof the gradually curved portion and forming a steep curve such that theother end thereof becomes near to the rotation shaft; and guide recessesformed in the gradually curved portion and the steep curved portion. 32.The compound bow according to claim 11, wherein the stopper memberincludes a housing having an upper portion to which the bowstring isconnected, a central portion to which the balance cable pulley isrotatably installed, and a protrusion protruding from the other side bya predetermined length at a lower portion thereof; and a latch, fixed tothe protrusion and having a locking hook for temporally fixing a lockingring which is installed at one side of the balance cable near to themain pulley from the balance cable pulley.
 33. The compound bowaccording to claim 32, wherein the latch is rotatably coupled to theprotrusion and further includes a locker which is protruded to control arotation; and the stopper member further includes a detent rotatablyinstalled to the protrusion and having a locking step temporallycontacting the locker of the latch to control the rotation of the latch,and a knob pin protruding toward the outside of the housing.
 34. Thecompound bow according to claim 33, wherein the stopper member furtherincludes a first torsion spring pressing the latch to be rotated in thedirection that the locking hook is locked with the locking ring; and asecond torsion spring pressing the detent in the direction where thelocker is supported by the locking step.
 35. The compound bow accordingto claim 34, wherein the knob pin of the detent further comprises arelease wire having one end to which the cam cable is connected and theother end to which the knob pin of the detent is coupled such that thelocking ring locked by the locker is separated during the rotation ofthe detent after an arrow is shot.
 36. The compound bow according toclaim 32, wherein the auxiliary pulley further comprises a stopping pinwhich is installed to the auxiliary pulley and temporally contacts themain body when the auxiliary pulley rotates by a predetermined anglesuch that the auxiliary pulley does not rotate further.
 37. The compoundbow according to claim 36, wherein the auxiliary pulley further includesan interference pin which moves along an movement hole formed in themain pulley.
 38. A compound bow comprising: a main body having a handlegrasped by a user, and a pair of limbs coupled to both ends of thehandle; a dual pulley including a main pulley rotatably installed on arotation shaft fixed to one end of the main body, and an auxiliarypulley having a radius greater than that of the main pulley androtatably installed on the rotation shaft; a cam installed to the mainpulley; a balance cable, both ends of which are fixed to the main pulleyand the auxiliary pulley and wound around the main pulley and theauxiliary pulley in the same direction; a stopper member, including abalance cable pulley which is installed at one end thereof and aroundwhich a central portion of the balance cable is wound, and temporallyfixing the balance cable when an arrow is shot; a cam cable having oneend fixed to the other end of the main body and the other end fixed tothe main pulley, and being wound around the cam in the directionopposite to that of the balance cable; a driven pulley rotatably fixedto the other end of the main body; and a bowstring having one endconnected to the stopper member and wound around the driven pulley, andthe other end fixed to the main pulley and wound around the cam in thedirection opposite to that of the cam cable.
 39. The compound bowaccording to claim 38, wherein the stopper member includes a housing, toan upper portion of which one end of the bowstring is coupled and to oneside of a central portion of which the balance cable pulley is rotatablyinstalled; and a stopper, formed at a lower side of the housing,including a locking hook by which a clip is caught to be temporarilyfixed, wherein the clip is mounted at one side of the balance cable nearto the main pulley from the balance cable pulley.
 40. The compound bowaccording to claim 39, wherein the stopper is rotatably coupled to thehousing, and further includes a locker of a stepped shape so that theclip is fastened by the locking hook by restricting the rotation of thestopper when the arrow is shot; and the stopper member further includesa trigger having a locking step which is formed at one end thereof andtemporarily contacts the locker of the stopper to control the rotationof the stopper.
 41. The compound bow according to claim 40, wherein thetrigger having the locking step formed at one end thereof is rotatablycoupled to the housing; and the stopper further includes a pushingsection which is spaced at a predetermined distance from and protrudesfrom the locking hook so that an upper portion of the clip contacts thestopper for its rotation when the clip moves into the housing; and asupport, of which one end is engaged with the stopper, and of which theother end contacts the other side of the trigger to rotate the triggeraccording to the rotation of the stopper and makes the locking step becaught to the locker.
 42. The compound bow according to claim 41,wherein the trigger further includes a contact which is formed at theother end thereof and contacts the balance cable near to the auxiliarypulley from the balance cable pulley, by which the balance cable rotatesthe trigger to have the locking step be separated from the locker whenthe balance cable is rewound around the main pulley and the auxiliarypulley after the arrow is shot.
 43. The compound bow according to claim38, wherein the auxiliary pulley further comprises a stopping pin whichis installed to the auxiliary pulley and temporally contacts the mainbody when the auxiliary pulley rotates by a predetermined angle suchthat the auxiliary pulley does not rotate further.
 44. The compound bowaccording to claim 43, wherein the auxiliary pulley further includes aninterference pin which moves along an movement hole formed in the mainpulley.
 45. The compound bow according to claim 43, wherein the stoppermember includes a housing, to an upper portion of which one end of thebowstring is coupled and to one side of a central portion of which thebalance cable pulley is rotatably installed; and a stopper, formed at alower side of the housing, having a locking hook by which a clip iscaught to be temporarily fixed, wherein the clip is mounted at one sideof the balance cable near to the main pulley from the balance cablepulley.
 46. The compound bow according to claim 45, wherein the stopperis rotatably coupled to the housing, and further includes a locker of astepped shape so that the clip is fastened by the locking hook byrestricting the rotation of the stopper when the arrow is shot; and thestopper member further includes a trigger which is formed at one endthereof and has a locking step temporarily contacting the locker of thestopper to control the rotation of the stopper.
 47. The compound bowaccording to claim 46, wherein the trigger having the locking stepformed at one end thereof is rotatably coupled to the housing; and thestopper further includes a pushing section which is spaced at apredetermined distance from and protrudes from the locking hook so thatan upper portion of the clip contacts the stopper for its rotation whenthe clip moves into the housing; and a support, of which one end isengaged with the stopper, and of which the other end contacts the otherside of the trigger to rotate the trigger according to the rotation ofthe stopper and makes the locking step be caught to the locker.
 48. Thecompound bow according to claim 47, wherein the trigger further includesa contact which is formed at the other end thereof and contacts thebalance cable near to the auxiliary pulley from the balance cablepulley, by which the balance cable rotates the trigger to have thelocking step be separated from the locker when the balance cable isrewound around the main pulley and the auxiliary pulley after the arrowis shot.
 49. The compound bow according to claim 45, wherein theauxiliary pulley further includes an interference pin which moves alongan movement hole formed in the main pulley.
 50. The compound bowaccording to claim 38, wherein the main pulley and the auxiliary pulleyare eccentrically installed on the rotation shaft.
 51. The compound bowaccording to claim 38, wherein the cam includes: a gradually curvedportion with an arc-shape; a steep curved portion connected to one endof the gradually curved portion and forming a steep curve such that theother end thereof becomes near to the rotation shaft; and guide recessesformed in the gradually curved portion and the steep curved portion. 52.The compound bow according to claim 38, wherein the stopper memberincludes a housing having an upper portion to which the bowstring isconnected, a central portion to which the balance cable pulley isrotatably installed, and a protrusion protruding from the other side bya predetermined length at a lower portion thereof; and a latch, fixed tothe protrusion and having a locking hook for temporally fixing a lockingring which is installed at one side of the balance cable near to themain pulley from the balance cable pulley.
 53. The compound bowaccording to claim 52, wherein the latch is rotatably coupled to theprotrusion and further includes a locker which is protruded to control arotation; and the stopper member further includes a detent rotatablyinstalled to the protrusion and having a locking step temporallycontacting the locker of the latch to control the rotation of the latch,and a knob pin protruding toward the outside of the housing.
 54. Thecompound bow according to claim 53, wherein the stopper member furtherincludes a first torsion spring pressing the latch to be rotated in thedirection that the locking hook is locked with the locking ring; and asecond torsion spring pressing the detent in the direction where thelocker is supported by the locking step.
 55. The compound bow accordingto claim 53, wherein the knob pin of the detent further comprises arelease wire having one end to which the cam cable is connected and theother end to which the knob pin of the detent is coupled such that thelocking ring locked by the locker is separated during the rotation ofthe detent after an arrow is shot.
 56. The compound bow according toclaim 52, wherein the auxiliary pulley further comprises a stopping pinwhich is installed to the auxiliary pulley and temporally contacts themain body when the auxiliary pulley rotates by a predetermined anglesuch that the auxiliary pulley does not rotate further.
 57. The compoundbow according to claim 56, wherein the auxiliary pulley further includesan interference pin which moves along an movement hole formed in themain pulley.
 58. A compound bow comprising: a main body having a handlegrasped by a user, and a pair of limbs coupled to both ends of thehandle; rotation shafts fixed to both ends of the main body,respectively; dual pulleys, each including a main pulley rotatablyinstalled on the rotation shaft fixed to one end of the main body, andan auxiliary pulley having a radius greater than that of the main pulleyand rotatably installed on the rotation shaft; cams, each installed tothe main pulley; balance cables, both ends of which are fixed to themain pulley and the auxiliary pulley and wound around the main pulleyand the auxiliary pulley in the same direction; stopper members, eachincluding a balance cable pulley which is formed at one side thereof andaround which a central portion of the balance cable is wound, andtemporally fixing the balance cable when the arrow is shot; cam cables,each having one end which is fixed to any one of both ends of the mainbody and the other end which is fixed to the main pulley formed at therotation shaft installed to the other end of the main body, and beingwound around the cam in the direction opposite to that of the balancecable; and a bowstring, of which both ends are connected to the stoppermembers.
 59. The compound bow according to claim 58, wherein the stoppermember includes a housing, to an upper portion of which one end of thebowstring is coupled and to one side of a central portion of which thebalance cable pulley is rotatably installed; and a stopper, formed at alower side of the housing, including a locking hook by which a clip iscaught to be temporarily fixed, wherein the clip is mounted at one sideof the balance cable near to the main pulley from the balance cablepulley.
 60. The compound bow according to claim 59, wherein the stopperis rotatably coupled to the housing, and further includes a locker of astepped shape so that the clip is fastened by the locking hook byrestricting the rotation of the stopper when the arrow is shot; and thestopper member further includes a trigger having a locking step which isformed at one end thereof and temporarily contacts the locker of thestopper to control the rotation of the stopper.
 61. The compound bowaccording to claim 60, wherein the trigger having the locking stepformed at one end thereof is rotatably coupled to the housing; and thestopper further includes a pushing section which is spaced at apredetermined distance from and protrudes from the locking hook so thatan upper portion of the clip contacts the stopper for its rotation whenthe clip moves into the housing; and a support, of which one end isengaged with the stopper, and of which the other end contacts the otherside of the trigger to rotate the trigger according to the rotation ofthe stopper and makes the locking step be caught to the locker.
 62. Thecompound bow according to claim 61, wherein the trigger further includesa contact which is formed at the other end thereof and contacts thebalance cable near to the auxiliary pulley from the balance cablepulley, by which the balance cable rotates the trigger to have thelocking step be separated from the locker when the balance cable isrewound around the main pulley and the auxiliary pulley after the arrowis shot.
 63. The compound bow according to claim 58, wherein theauxiliary pulley further comprises a stopping pin which is installed tothe auxiliary pulley and temporally contacts the main body when theauxiliary pulley rotates by a predetermined angle such that theauxiliary pulley does not rotate further.
 64. The compound bow accordingto claim 63, wherein the auxiliary pulley further includes aninterference pin which moves along an movement hole formed in the mainpulley.
 65. The compound bow according to claim 63, wherein theauxiliary pulley further includes an interference pin which contacts aninterference step formed in the main pulley.
 66. The compound bowaccording to claim 63, wherein the stopper member includes a housing, toan upper portion of which one end of the bowstring is coupled and to oneside of a central portion of which the balance cable pulley is rotatablyinstalled; and a stopper, formed at a lower side of the housing, havinga locking hook by which a clip is caught to be temporarily fixed,wherein the clip is mounted at one side of the balance cable near to themain pulley from the balance cable pulley.
 67. The compound bowaccording to claim 66, wherein the stopper is rotatably coupled to thehousing, and further includes a locker of a stepped shape so that theclip is fastened by the locking hook by restricting the rotation of thestopper when the arrow is shot; and the stopper member further includesa trigger which is formed at one end thereof and has a locking steptemporarily contacting the locker of the stopper to control the rotationof the stopper.
 68. The compound bow according to claim 67, wherein thetrigger having the locking step formed at one end thereof is rotatablycoupled to the housing; and the stopper further includes a pushingsection which is spaced at a predetermined distance from and protrudesfrom the locking hook so that an upper portion of the clip contacts thestopper for its rotation when the clip moves into the housing; and asupport, of which one end is engaged with the stopper, and of which theother end contacts the other side of the trigger to rotate the triggeraccording to the rotation of the stopper and makes the locking step becaught to the locker.
 69. The compound bow according to claim 68,wherein the trigger further includes a contact which is formed at theother end thereof and contacts the balance cable near to the auxiliarypulley from the balance cable pulley, by which the balance cable rotatesthe trigger to have the locking step be separated from the locker whenthe balance cable is rewound around the main pulley and the auxiliarypulley after the arrow is shot.
 70. The compound bow according to claim66, wherein the auxiliary pulley further includes an interference pinwhich moves along an movement hole formed in the main pulley.
 71. Thecompound bow according to claim 58, wherein the main pulley and theauxiliary pulley are eccentrically installed on the rotation shaft. 72.The compound bow according to claim 58, wherein each of the main pulleyand the auxiliary pulley includes a guide recess, depressed from theouter circumference thereof, around which the balance cable is wound;and the auxiliary pulley includes a separation preventing unitprotruding along the guide recess by a predetermined height to preventseparation of the balance cable.
 73. The compound bow according to claim58, wherein the main pulley further comprises an anti-vibration guidewhich is formed at one side of the outer circumference thereof and has aguide recess installed in the tangential direction of the outercircumference thereof.
 74. The compound bow according to claim 58,wherein the cam includes: a gradually curved portion with an arc-shape;a steep curved portion connected to one end of the gradually curvedportion and forming a steep curve such that the other end thereofbecomes near to the rotation shaft; and guide recesses formed in thegradually curved portion and the steep curved portion.
 75. The compoundbow according to claim 58, wherein the stopper member includes a housinghaving an upper portion to which the bowstring is connected, a centralportion to which the balance cable pulley is rotatably installed, and aprotrusion protruding from the other side by a predetermined length at alower portion thereof; and a latch, fixed to the protrusion and having alocking hook for temporally fixing a locking ring which is installed atone side of the balance cable near to the main pulley from the balancecable pulley.
 76. The compound bow according to claim 75, wherein thelatch is rotatably coupled to the protrusion and further includes alocker which is protruded to control a rotation; and the stopper memberfurther includes a detent rotatably installed to the protrusion andhaving a locking step temporally contacting the locker of the latch tocontrol the rotation of the latch, and a knob pin protruding toward theoutside of the housing.
 77. The compound bow according to claim 76,wherein the stopper member further includes a first torsion springpressing the latch to be rotated in the direction that the locking hookis locked with the locking ring; and a second torsion spring pressingthe detent in the direction where the locker is supported by the lockingstep.
 78. The compound bow according to claim 76, wherein the knob pinof the detent further comprises a release wire having one end to whichthe cam cable is connected and the other end to which the knob pin ofthe detent is coupled such that the locking ring locked by the locker isseparated during the rotation of the detent after an arrow is shot. 79.The compound bow according to claim 75, wherein the auxiliary pulleyfurther comprises a stopping pin which is installed to the auxiliarypulley and temporally contacts the main body when the auxiliary pulleyrotates by a predetermined angle such that the auxiliary pulley does notrotate further.
 80. The compound bow according to claim 79, wherein theauxiliary pulley further includes an interference pin which moves alongan movement hole formed in the main pulley.
 81. The compound bowaccording to claim 79, wherein the auxiliary pulley further includes aninterference pin which contacts an interference step formed in the mainpulley.